Bombing camera



May 1 9, 1942;

A. BVRIECHLE ET AL BOMBING CAMERA Filed March 22, 1938 10 Sheets-Sheet l INVENTORS CM, P

A. BRIECHLE ETAL May 19, K 1942.

BOMBING CAMERA Filed March 22, 1958 10 Sheets-Sheet 2 IIS IIS

m/ENT'ORJl sx-J l May 19, 1942.

A. BRIECHLE ET AL BOMBING CAMERA Filed March 22, 1938 l0 Sheets-Sheet 3 (ma ma |04 5 INVENTORS ATORNEY.

May 19, 1942.

ABRIECHLE. ET AL BOMBING CAMERAl FiledAV March 22, i938 l Sheets-Sheet 4 INVENTORS EES 10 Sheets-Sheet 5 'BOMBING CAMERA n Filed March 22, 1958 EE u Y INVENToRs 3%( ATTORNEY.j

May 19, 1942.

May 19, 1942, A. BRIECHLE ET AL BOMBINGCAMERA Filed March 22, 1958 l0 Sheets-Sheet 6 INVENTORS ATTORNEY.

lam I 1o sheets-sheet BOMBING CAMERA Filed March 22, 1938 A. BRIECHLE ET AL I n n May 19, 1942.

BY Mw( w71 c",

mmmmmy.

May 19, 1942. A. BRIECHLE Erl-A1. 2,283,788

' BOMBING cin/VERAv Filed March 22, 1958 1o sheets-sheet a IN VENORS 1o sheets-sheet 9 ze Y BOMBING CAMERA A. BRIECHLE ET AL Filed March 22,. 1958 May 19, 1942.

- INVENTR.

` MCM ATTORNEY.

Patented May 19, 1942.

UNi'rliDv STAT as PATENT,

y oFFlcE y 'noni/BIN@ CAMERA Ambrosius Briechle, Brooklyn, Boy T. 'Hurley'.- Dobbs Ferry', N. Y., and George E. Merritt,

p Lsby, Md., assignors to Bendix Aviation Cor- I poration, South ,'Bend, Ind., a corporation ofl DelawareV appucationimrcnzz,193s, serial No'. 197,402

z claims.

y whereby the film is -lxed in the focal plane oi' the lens and in predetermined relation to theoptical axis of said lens.

Still another object of the present invention is to provide novelinterval meter means for automatic .control ot the release of camera shutter means. Y Another object is to provide novel means, including a pressure plate, operable in combination with the magazine and the cone to fir: the iilm in the focal plane. Another object. is to provide novel fluid pressure means in combination with the pressure operating position and showing the iluid conduit connectionvfrom the. cone to the magazine; v

' Fig. 6 is sectional view taken substantially on line 5'-6 of Fig. 3 with the cone and cover in 5 operating position; v

Fig? 7 Fig. 6;

Fig. 8 iS a is a similarview taken on line 1--1 of ysectional view taken substantially on line 8--8 of Fig. 3 and showing-a means'for p locking the pressure plate against accidental or inadvertent movement after removal otthe'cone; Fig. 9 is a sectional view taken substantially on line 9--9 o! Fig. '7; l Fig. 10 is a top plan view, with parts broken away and partly in section, the section being taken substantially on line lll-lllvr otFig. 1;

Fig. 10a is an enlarged sectional viewk taken substantially 'along line loaf-Ilia of Fig. 10;

. Fig. 11 is a detail sectional' view, with parts .broken away, taken substantially on line ll-II of Fig. 10; y

Fig. 12 is a sectional view taken substantially Fig. 13 is a similar view takenfon, une ls-n of Fig. 10;

plate for holding the film in a true and predetermined plane.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is taken in connection with the accompanying i drawings. It is to be expressly understood, however, that the drawings' are for the purpose of illustration only and are not intended to define the limits of the invention, reference being primarily had for this latter purpose to the aD- pended cl-aims.

In the drawings, wherein like reference characters refer to like parts throughout the several views, f

Fig. 1 is a front elevation, with parts broken away and partly in section, o1' one embodiment of the present invention, showing a' cone, a magazine and a cover in normal operative positions;

Fig. 2 is a sectional view ci' a part of the film roll drive taken substantially on line 2,-2 o! Figi; v

Y Fig. 3 is a detail top plany view of the magazine .with the 'cover removed;

Figui is a rear elevation o! the magazine with the cone and cover removed and with parts -broken' away to show the details of the counter structure;

Figi-15 a sectional view taken substantially 'online 5-5 of Fig. 3 with the cone and cover in,

Fig. 14 is a sectional view with parts broken away taken substantially on line I/l--M oi' Fig. l, showing, partly in plan and partly in secticnfthe shutter mechanism and ,the control and drive 39 therefor;

Fig. 15 is a somewhat enlarged rear elevation,

vpartly in section, showing a form of spring drive utilized for motivating the shutter rolls;

f Fig. 16 is asimilar view taken substantially on 35 line IB-IG of Fig. 14;

kf Fig. 17 is a somewhat enlarged sectional View,`

takenr substantially on line l1-l1 of Fig. 14

showing -a form of cam means adaptable for releasing the shutter curtain: 1

Fig. 18 is a similar view taken substantially on line |8|8 of Fig. 14;

Fig. 19 is 1a sectional view taken substantially' on line l9-I9 of Fig. 14 showing the relative positions of the shutter mechanism and the lenses;

Fig. 20 is a lateral, substantially central, sectional view of the completely assembled camera showingthe lens structure partly in elevation and partly in section; 1

Fig. `2l is a sectional view taken substantially along line-Zl-ZI of Fig. .22 showing one form of electrical motor adapted for driving the various camera mechanisms; l

Fig. 22 is Ian end sectional view taken substantially along line 22-22 of Fig. 21; Q I

Fig. 23 isa side elevationwith parts broken away and partly in section of the assembled.` camera showing an interval meter andthe motor mounted in operative position;

Fig. `24 is a section through the interval meter taken substantially alongline 24-24 of Fig. 23, andshowing the, operating parts thereof in top plan view; Fig. 25 is a` sectional view taken substantially along line 25-25 of Fig. 24;

Fig. 26 is a front elevation of the meter with parts broken away:

Fig. 27 is a sectional view taken substantially along line 21-21 of Fig. 26;

n Fig. 28 is a'sectional view taken substantially along line 28-28 of Fig. 27 and showing the motor for driving the interval meter Fig. 29 isa longitudinal sectional view through the camera with parts broken away showing the auxiliary optical system for photographically recording bombing data; Fig. 30 is a section taken substantially along line 30-30 ofmFig. 29 showing the details of the optical system a'nd the film maintaining' and metering means;i i

Fig. 31 is a sectional view taken substantially along line 3I-3i of Fig. 29 showing the various -instruments for giving the data to be recorded;

Fig. 32 is a sectional view with parts broken away taken substantially along line 32-32 of Fig. 3 1 and showing in detail the manner in which one -of the instruments is mounted; and.

Fig. 33 is adiagram of one form of electric circuit suitable for` energizing the drive and control mechanisms.

In the illustrated embodiment,` the camera of the present invention is shown as having two major sections, i. e.. a magazine 23 in which the film is housed, suitablypositioned, and metered for exposure, and a cone 24 in .which the driving and control mechanisms, the shutter and the lenses are mounted. A cover 25 is provided for the magazine serving to keep said magazine dustand light-proof and to cooperate with parts of the magazine and perform other usefuly functions, to appear later. It will be lnoted that the section housing the film and the section housing the lenses are, by the present construction, adjacent each other permitting means, hereinafter more fully described, to be utilized which may fix the film plane independently of the accuracy with which the cone is mounted on said magazine. 4

` interval Magazine and cover Magazine 23 comprises a main casting 24 having two longitudinally spaced, upwardly extending walls 21 and 23v (Figs. l. 3 and 6), which walls, in combination with cover 25, form a lcentral chamber 29. in said magazine. Two 111m rolls 38 and 3i (Fig. 7) are adapted for rotation about fixed longitudinal axes in said chamber, and the unexposed nlm, preferably wound upon roll 38, is adapted to be unwound therefrom and exposed by means to be hereinafter more fully described.-

order to facilitate camera loading, this method of central support has been eliminated and novel means are provided whereby the film rolls are positioned for rotation about fixedl longitudinal axes by merely inserting the rolls into the magazine chamber in the` general direction of the final position which said rolls will assume. The novel means consist of a three-point support for each of the lm roll end pieces, two of said supports in each instance serving to determine the film roll position and the third applying the pressure to fix the end pieces of the rolls in position for rotation Lwith the supports.

' tudinally therebetween.

' rolls 34 and into engagement with the end provided in cover 25 been fixed for rotation in the magazines of said cameras by trunnions located at the centers of rotation. However.

in the present device, in

As shown in Figs. 3-and 7, mining the position oi` roll 30 shafts 32 and 33 which are tion in walls 21 and 28 and the supports deterare mounted on two joumalled for rotawhich extend longi- Mounted on the ends 32 adjacent the internal facesof and'28, respectively, are supporting 35 onwhich the en d pieces of nlm roll 38 are adapted to rotate. Similarly mounted for the same purpose on shaft 33 are rolls 38 and 31 and a smilar construction comprising shafts of the shaft the walls 21 .38 and 33 and supporting rolls 48, 4i, 42 and 43 is provided for mounting film roll 3|.

Placing the end pieces of each film roll on the supports hereinbefore described determines the longitudinal axes of rotation for the film rolls. However, to x the film roll end pieces so that they will remain in contact, and rotate with the supporting rolls, a third support adapted to be resiiiently held against the end pieces is provided. Rolls 44 and 45 (Figs. 3 and 7), secured to a shaft 48 for rotation lm roll 30 as the third support therefor, and are resiiiently urged by means of a pair of arms 41 and 48 into engagement with the end pieces oi' said nlm roll. Arms 41 and 48 support shaft 46 and are pivotally mounted on a second shaft 49 which,in turn, is Journalled in suitable bearings in an upper central portion 50 of the magazine casting. Portion 50 may be cast integrally with the main casting of the 'magazine or may be suitably aillxed to said casting between walls 21 and 28. In order to resillently urge rolls 44 and 45 pieces, a pair of light coil springs 5 i and 52 are wound about shaft 49. vEach of said springs has one end thereof bearing upon one of the arms 41 or 48 vand the other end thereof 4bearing upon portion 58 andeach tends to expand andl urge the arm with which it cooperates into engagement with lm roll 30. The force exerted upon said roll due to said springs is only sumcient to prevent said roll from falling out of said magazine when the same is inverted with cover' 25 removed, as for example, when the film is being threaded into position. A structure which is the duplicate of the above-described means for holding roll 30 in operative position is also provided for holding roll 3| and comprises coil springs 53 and 54, arms 55vand 53 pivotal about a shaft 51 and rolls 58 and 58 mounted upon a shaft B0. Other resilient means, in the form of a leaf spring a, are also being suitably secured thereto to have the spring ends bear against the central portions of shafts 45 and 58 and thereby yieldingly urge the supporting rolls mounted on After inserting nlm rolls 38 and 3i into the therewith, function to hold roll 62, fixed to shaft 32 (Fig. 9), then under a pressure plate 68, and thence over a metering drum 64 to film roll 3|, said metering drum being secured to and rotatable with shaft 38. The film is fixed to roll 3| by any suitable method, as, for example, by insertion ofthe end of the film into a slot arranged therefor in the cylinderl of said roll.

After the film has been loaded into the magazine in the manner above described, cover is placed thereon. 'Ihe Walls 21 and `28 (Fig. 6) have flanges 65 and 86, respectively, extending the length of the upper edges thereof and said flanges are adapted to fit into grooves 61 and 68, respectively, provided therefor incover 25 and to thereby form a light trap keeping light from entering chamber 29. Similar light traps between the lower edge of said coverand magazine 'casting 26, comprising flanges69 and 10 (Fig. '7) in said magazine and grooves 1| and12 in said cover, complete rthe means whereby chamber 29 is kept light-proof. To keep the magazine interior dustproof, an additional groove'1la is provided in main casting 26 along the edge thereof completely circumscribing the magazine interior and having a strip or washer 12a of some yielding substance such as rubber or felt fixed therein. The bottom of the cover when the latter is correctly positioned on the magazine'fits over said strip and compresses the same, thereby producing adust-proof joint or connection between said magazine and cone.

Novel means are provided for locking cover 25 to magazine 23 by merely placing said cover over during operation of the camera. As shown, said by said nut. Thumb screw `13 may be rotated thereafter to further increase the threaded engagement between nut 81 and portion 88, threading the latter into the former through the worm and gear 80, 82. A split nut means similar to that described above is provided for cooperatingA with worm,V and gear 8|, 83, so that rotation of shaft 14 by thumb screw 13 also controls the locking and releasing of said unit. Both units are unlocked for removal of the cover by rotation of shaft 14, said shaft operating the worm x and gear drives of the threaded shafts and causing rotation of said threaded shafts in a direction' to unscrew the same from the split nuts.

, In order to expose'a new frame of film after each photograph is taken, metering drum 64 is rotated through a predetermined angular distance after each exposure and novel means are provided for maintaining the film in contact with said drum during rotation thereof so that the film may be accurately metered thereby. The

of cover 25.

novel means comprise a pressure roll 90 (Fig. '1) suitably mounted on a shaft 9|' which is journailed at each end in a bracket 82, pivotally mounted by means of a pin 83 on the inner wall Resilient means, such as a leaf spring 94 are secured to said bracket, and when the cover is locked to the magazine, said resilient means urge` pressure roll 90 against metering drum 64 pressing the fihn into frictional engagement with said drum. By mounting the pressure roll on the cover, the necessity for threading the film' between rolls during loading is eliminated and the process of loading is accomplished more readily and vmore quickly than heretofore in cameras which had the pressure roll and the locking means comprises a shaft 14 mounted for rotation in bearings 15 and 16 located in walls 21 and 28, respectively, and in upwardly extending .lugs 11 and 18 (Figs. 6 and '1) cast integrally with or rigidly fixed to portion 58 of the magazine casting. Shaft 14 has a part thereof projecting outside of wall 21 and has thumb screw 13 mounted `on this projecting portion. A slot or opening 19 is provided in cover 25 in order that thumb,v screw 13 may extend through said slot and be operable from the exterior of said cover.

A pair of Worms 80 and 8|, preferably integral with shaft 14, are rotated thereby and are adapted to engage and rotate worm gears 82 and 83, respectively. Gear 82 is suitably secured to or integral with a vertical shaft 84 and the lower end of the latter extends through portion and is held against axial movement by means of a collar 85 afxed thereto. A portion 86 of said shaft also extends upwardly above gear 82 and is 'suitably threaded so that a split nut 81 secured to cover 25 may engage the same. ,Said nut is split into two segments, each of which is pivotally mounted in a casing 88 fixed to cover 25 and a coil spring 89 is wound about saidsegments to keep the same together and normally operative as a single nut. However, threaded portion 86 of shaft 84 may be made to engage the split nut without being screwed into said nut by having thelatter forced down upon it, thereby prying apart the segments of said nut against `the constricting force of coil'sprlng 88 and permitting said threaded portion to be grasped T5 meteringroll mounted in the magazine in fixed relation to each other.

Movement of the lm by means of metering drum 8f rotates .idler roll 82 and unwinds the film from film roll causing the latter to rotate in a clockwise direction as viewed in Fig. 7. In order to frictionally resist the free rotation of saidv film roll and keep the film under aslight tension so as to minimize the possibility of wrinkling, means, such as a friction disc (Fig. 9), are provided in the magazine for applying a frictional force which tends to retardthe rotation of film roll 3|?. A hollow boss 961s cast integrally with wall 21 of thev magazine and friction, disc is mounted on a rod s1 which extends through said boss and has a collar 98 secured to the outer cnd thereof. Disc t5 is held in frictional engagement with the end piece of roll 3.0 by the expansive force of coil spring 99 interposed between y said disc and the bottom of said boss and surrounding rod 91 within said boss. A pin |00 mounted 4in wall 21 and extendinginto an opening 10| in disc 95 holds said disc against rotary movement. A similar disc (not shown) is preferably provided in wall 2 8 directly opposite disc 95 for the other end piece of film'roll 3|). As a result, a pull must be exerted upon the film which is sufficient to overcome the resistance of the friction discs The latter, in addition to keeping the film taut. serve to center the film roll Ibetween the walls 21 and 28, this being one reason f why a pair of discs is provided.

y The film after passing from metering drum 34 is wound on roll 3 I, thek latter being frictionally driven by supporting rolls 40 and 4| (Figs. 2 and 3) on which the end pieces of said film roll rest. The end pieces are adapted to slip on said supporting rolls ,while being driven thereby because the speed at which said supporting rollsg tend to drive the film is in excess of the speed at which said film roll must rotate to'take up all the film passing from the metering drum, As a result, the film is kept `taut between said drum and said film roll while being wound upon the latter. I

Means located in the cone, to be hereinafter more fully described, are provided for driving the' mechanism which imparts rotary motion to the metering drum 04 for moving the film and to the two supporting rolls 40 and 4| for drivinggfilm roll 3|. vSaid mechanism comprises an ripper i casting by means comprising a pair of vertical member of a Jaw coupling |02 (Figs. 1` and 8) integral with or suitably fixed to a hollow shaft |03, said shaft being journalled for rotation in a set of ball bearings |04. A bevel gear |05 secured to the upper end of shaft |03 meshes with a bevel gear aiiixed to a' shaft |01 and is adapted to drive the latter which is journalled for rotation in suitable bearings mounted in a pair of downwardly extending arms |08, |08 of a bracket ||0. yThe latter is secured by screws to the outside face oi' wall 21 of the magazine cast- `,ing. j

v'I'o actuate supporting rolls 40 and 4|, a shaft I |2 is drivably connected to shaft |01 by means of a pairA of engaging helical gears ||3 and H4, the former being fixed to shaft. |01 andthe latter to the end of shaft ||2. The latter extends through and isfjournalled for rotation in walls 21 and 28 and has secured thereto a pairof spur gears ||5 and ||0 (Fig. 3), gear ||5 (Fig/2) being mounted adjacent the outside face of wall 2.1 and meshing with spur gear ||1. Theilatte'r is keyed to the hub of supporting roll 40, which bears on but rotates freely of shaft 39, and drives said roll. Spur gear ||0 (Fig: 3) is similarly mounted adjacent the outside face of wall 28 and meshes wtih gear H8, to drive supporting roll 4| at the same speed and in the same lmanner as roll 40 is driven. Accordingly, lm roll 3| is driven at both ends by supporting rolls 40 and 4| and` applies .a uniform force across the width of the film during the Winding thereof.

Metering drum 04 is rotated by a worm ||0 (Figs. 1 and 8) fixed to shaft |01- and a worm 'wheel |20 fixed to shaft 39, the latter shaft having said drum secured thereto for rotationtherewith. The worm drive rotates drum 04 at a slower speed than the helical` drive through which supporting rolls 40 and 4| are driven, producing the tension in the portion of film between y' said metering roll and the film roll.

In orde/r to provide exact andclear vphotographs, a high degree of accuracy in fixing the film plane, so that it coincides with the focal accurately finished in a plane and the lenses are subsequently adjusted to have the focal plane the pronged end of arm |30 (Fig. 7).

n plane, is necessary. Novel means, mounted in the arms or rods |24 and |25 (Fig. 6), mounted in recesses provided therefor in said pressure plate and held in said recesses by pins |20 and |21, respectively. A pair of inwardly extending lugs |28 and |20 castintegrally with wall 21 areprovided having openingssuitably bored therein in which rod |24 is slidably mounted and which guide said rod in any vertical movement thereof. A collar |30 is fixed `to rod 24 between lugs |28 and |29 and a compressed coil spring I 3| 'is mounted between said collar and upper lug |20,

surrounding said rod and exerting an expansive l force upon collar |30 which tends to move plate 03 in `a downward direction into contact with cone surface |2|. A `similar structure to that above described, comprising lugs |32 and |33, coil spring |34 and collarl, is provided in combination with rod |25 and exerts a downward force, augmenting the forceof spring |3| upon the pressure plate. Rods |24 and |25 are loosely mounted in the openings provided therefor in the guiding lugs, anappreciable clearance existing between said openings and said rods in order that the base plane of the pressure plate may be aligned by the plane of finished surface |2| when brought in contact therewith 'even though .the magazine is slightly askew in relation to the cone. As a result, pressure plate 63 is normally yieldingly held in the plane of finished surface 2|, i. e., the focal plane of the camera lenses, and positions the film accordingly.

photograph has been taken, the force normally exerted upon the film by pressure plate 03 must be overcome s0 that metering roll 04 may move the film. (Accordingly, means are provided whereby pressure plate 03 is raised against the force of springs 3| and |34, relieving the pressure upon the film and permitting free movement thereof, said means, as shown, comprising a pair of arms or levers |30 and |31 which extend into slots |38 and |39,` respectively. Slot |38 is adjacent to rod |24, being suitably positioned in the pressure plate casting to have pin |20 extend therethrough and to have said pin engaged by Arm |31 similarly engages pin |21 and is, together with arm |30, secured to a shaft for rotation therewith. Shaft |40 is journalled in walls 21 and 28 and has a portion thereof extending outside 1, 3, 6, and 8).

' shaft ,|40 by transmitting thereto the reciprocal thereof coincide with said'plane. Pressure plate 03 is preferably a metal casting, substantially rectangularin shape, having its lower face finished and grooved and being of sufficient size to cover an opening |22 in the upper end ofthe cone casting. The film is urged into contact with the'- base of said pressure plate by means to be de` scribed hereafter, and the sensitive side of said film is exposed ln the direction of opening |22 so that a photographic impression may be made motion of a rod |42 (Fig. 8) so that whenever rod |42 is raised, lever |4| rotates in a counterclockwise direction and likewise moves arms |36 and |31 thereby lifting pressure plate 03 sufficiently to clear the path of the film travel.

Rod |42 which reciprocatesand actuates the abovedescribedmechanism for raising pressure plate 03 is mounted concentrically with shaft R33 in the hollowed center thereof. The reciproca! movement is imparted t0 said rod by cam means, to be hereinafter more fully described, said means being suitably timed to move rod |42 in an upward direction raising pressure plate 03 once after each exposure and keeping said pressure In order to expose a new frame of film after a Y Lever |4I is adapted to rotate' plate in a raised position during the interval in.

which the exposedframe of nlm is displaced by.l

an unexposed frame. When said unexposed film frame has been suitablypositioned between said pressure plate and surface |2`| ofthe cone, the

former is lowered into engagement with the latter and frictionally holds the film in the focal plane.

In order to eliminate any wrinkles' or creases existent 1in the film after, lthe same has been moved by metering roll 64 into position` under creasing, and also to definitely fix the fllm in the focal plane, the same novel means are used a second time and urge the nlm into contact with the pressure plate when the shutter mechyanism releases the shutter curtain to expose the film. l

The novel fiuidipres'sure means comprise rra series' of longitudinal and lateral channels orv .grooves |43 machined or cast in the base plane of pressure plate 63 in such a Vmanner that when f in the cover.

by utilizing suitable'pressure means to create a pressure above atmospheric in the camera cone and by opening grooves |43 to the atmospheric pressure in the magazine, thereby-producing a pressure differential tending to force the nlm ijnto contact with the pressure plate.

In order to indicate the number Vof exposures made upon the i'llm, a counter (Figs. 3, 4, and 6) is provided in the magazine *and is adapted to register each exposure bythe movement of calibrated drum |54 past stationary index mark |55, said drum .and mark being visible through a window |56 (Fig. 6) conveniently positioned A casing |51 surrounds drum |54 exposing only the vportion visibler through window |56 and as shown is attached to wall 28 by a screwl |58. A ratchet wheel |59 (Figs.'3 and 4) is integral wither suitably fixed to drum |54 and is provided with a hub member |60, the unit being rotatably mounted on a shaft ||i| iixedbetween casing |51 and magazine wall a pianey surface of any nature is brought into,

` lcontact with the base plane of said pressure plate,

said grooves constitute a group of fluid conduits each of which is connected to every other. An annular flange |44 (Figs. 6 and 7) preferably located at the center of pressure plate 63, is cast integrally with the upper surface of said pressure plate and has a cap or cover plate |45 secured thereto by means such as screws |46. Cap |45 isipreferably formed with a raised central portion |41 and together with flange |44 constitutes a fluid chamber |48 `which is connected by a number of openings orpassages |49 to grooves |43. A flexible conduit |50 is suitably positioned to communicate with chamber |48 'v and, as shown, is threadedly secured at one end to upper portion |41 of cap |45 and at the other end to a part of the' magazine casting (Fig. 5). A passage |5| in said casting is adapted to connect flexible conduit to a second flexible conduit |52\ when the cone and magazine are operatively assembled. A suitable washer |5|a is interposed between conduit |52 and the` end adapted to regulate the pressure therein. Byv

, decreasing the pressure in said chamber to subatmospheric pressure, a suction is created in grooves |43 whereby the film, even though loosely stretched across the base of pressure plate 63 is forced into contact with said base. In this manner, the nlm is nxed in the plane of the is in lowered position and supported -by nnished surface |2I,A said base plane in which the .film is fixed is coincident with the focal plane. Said pressure means also operates to fix the film in.. the focal plane immediately prior to the release of the shutter mechanism. It will be understood that the-above-described results may be produced 28. A coil spring`l |62 having `one end thereof secured to a flange |63 .on hub member |68 and the other end fixed to wall 28, normally opposes rotary movement of ratchet wheel |59 and a1` ways tends to return drum |54, after rotation of the same, to zero position.

Since the pressure plate and, therefore, rods |24 and |25, are raised once for every exposure. every upward movement of .said rod |25 isutilized in the present invention to motivate the means for rotating ratchet wheel |59 and drum |54 to indicate another exposure. Said means comprise a lever |64 (Fig. 4) having a bifurcated end which flts into` a slot |65 provided therefor in arm |25, and which engages a pin |66 fixed to said arm and extending through said slot. The other end of -lever |64 is secured to a shaft |61 which is journalled in and extends through wall 28and which has a second lever |68 fastened thereto onthe other side of said wall. Levers |64 andv |68 and shaft |61 rotate as a unit and, therefore, when arm'l'25 moves upward, lever |68, on the opposite side of the fulcrum moves downward. `A pawl |69, pivotally mounted on the end of lever |68 and resiliently urgedv bya spring |18 in the direction of ratchet wheel |59, engages said Wheel when said lever is moved downward and rotates the former a predetermined number-of notches, thereby ro' tating drum Y|54 a single graduation past index mark |55. When lever |68 is moved upward, moving pawl |69 therewith, a pin 1|, fixed to wal128 and extending perpendicularly therefrom, is adapted to engage pawl |69 and causethe same to disengage from ratchet wheel |59.

Novel means, rendered operable byi pressing cover 25 into locked position with magazine 23, are provided for holding ratchet Wheel |59 against rotation by spring |62, in a direction to return indicating drum |54 to a zero reading. Said means comprise a cantilever spring |12 fixed to casing |51 and having a curved end extending downwardly in the direction of ratchet wheel |59, said endbeing adapted to hold said wheel, asy viewed in Fig. 4, against rotation in `base of said pressure plate and when the latter a counter-clockwise direction, when moved into engagement therewith. A member |13 slidably mounted in casing |51 is supported by spring |12 and when cover 25 isremoved extends beyond the upper surface of said casing. However,

when said cover is replaced, a part thereof, in

the form of lug |14 (Fig. 6) bears against and i53. As a result, whenevercover 2l is -removed- After a film roll has been fully exposed or perhaps during exposure thereof, an occasion for removal of the magazinef from the cone may bination with pressure plate actuating lever |4| for holding the pressure plate in lowered position against the magazine casting.' thereby preventing admittance of light into the magazine` The novel latch comprises a lever 335b (Figs. 1 and 3) pivotally mounted intermediate the ends thereof to lever |4| in a substantiallyvertical'position. The upper end of lever 335 is resilientlyurged, by a spring 338 nxed between said endand lever I4 I, to move in a clockwise direction. 'I'he lower endof lever 335 extends. through an opening `331 in the magazine base and is provided with a pair of notches or openings 338 and 333, the former being positioned above the latter, and being adapted to engage a plate 343 suitably affixed to the base of the magazine and projecting beyond opening 331. With the cone removed, pressure plate 83 is in lowered position' and spring 333 urges lever 335\in a direction to have plate 343 engage notch 333 and hold the pressure plate in the lowered position against any accidental or inadvertent raising thereof. When the cone is fixed to the magazine, a lug 34| shown in broken lines in Fig. 8 engages the lower end of lever 335 and moves said lever and the notches therein away from plate 343, and'out of engagement with said,plate, thereby leaving actuating lever |4| unaffected during the cyclic operations.

It is often desirable', as, for example, when threading the illm from roll Y33 to roll 3|, to have pressure plate 83 held in .raised position, and'for this purpose, notch 333 is provided in lever K335. After removal of the magazine, lever 335 may be manually operated and raised' so that notch 333, instead of notch 338, engages plate 343, thereby holding actuating lever |4| and pressure plate 83 in raised position.

Cone

Cone 24 comprises a central casting |15 substantially square in horizontal cross-section and preferably having each side thereof similar in contour to the shape of the side shown -in secf tion in Fig. 1l.. A casing |18, amxed to saidy casting and surrounding the same, encloses the drivf.

ing and control mechanisms, to be hereinafter more fully described, which are mountedjon said I outside of casing |13.. Rotation of shaft |11by y thumb screw |18 causes axial movement of members |13 'into which ends |83 of said shaft Vare threaded, said members being slidably mounted in casting |15 and constrained to axial movement by pins |3| fixed therein and radially extending therefrom, into longitudinal grooves |32 in said casting. The longitudinal displacement .ofmernberszl13 caused by rotation of thumb mesh with said spur gear.

nected by spring coupling |350. to gear |33, said yscrew I13Qmoves said members int'o or out of openings |83 provided therefor in magazine 23 and locks or unlocks cone 24 into or from operative position upon said magazine. In the embodiment illustrated, a second lock, of like construction to the above, is provided in the cone, and engages the oppositeside of magazine 23.

g The camera is operable either by manual or motor means and is shown as having a readily l0 accessible hand crank |34 and a motor |840., arise. A novel safety latch is provided in com- ,Y

either of which may beutilized for actuating the driving andcontrol mechanisms of the camera. Crank |34 1s mounted on a shaft |35 and directly rotates, when turned, a bevel gear |33 which is 15N`forrned with or secured to said shaft (Figs. 1

and l0).v Bevelfgear |33 meshes with `a second bevel gear |31 and thereby drives.'through spur gear |33, the latter two gears being mounted on the same shaft, two gears |83 and |33, which Motor |34a is concoupling being of the type adapted to transmit a torque in only one direction, i. e., making ya driving connection from the motor lto the gear only.

In :the illustrated embodiment, motor |34a is suspended from the upper part of cone casting |15 by means such as screws |88a and comprises a casting |81a (Figs. 2l and 22) in which an 3o armature |33a is supported by ball bearings |83a.

The usual field winding |330. is provided, and,

a shaft |3|a rotates withI armature |83a and has a worm |32a formed integrally'therewith. The latter engages and drives ageanla opera- 35 tively connected to coupling |35a, thereby driving gear |33.

Gear |33 is integral with or suitably keyed to a shaft |3|, said shaft being mounted for rotation in downwardlyext'ending brackets `|32 and 40 having a worm |33 and a Jaw clutch plate |34 mounted thereon. Clutch plate |34 is adapted ,f to operatively engage a corresponding plate |35 amxed to a second shaft |31 and to drive said second shaft. when so engaged; Shaft |33 extends through and is journalled in brackets |31 and has a bevel gear |33 mounted thereon which meshes with a second bevelfgear`|33, the latter being secured to a hollow shaft 233, and thereby `being adapted to drive the lower member of jaw coupling `|32 which is also secured to said hollow shaft. Jaw coupling |32 has'the upper and lower portions thereof operatively engaged and directly connecting shafts 4233'and |33 when the cone is locked to the magazine.

As nerembefore described; 'shaft m, when fdriven through coupling |32,vactuates the mechanism which-meters the film and said film is metered during only'a predetermined portion of the time necessary for the perfomance of the ,m complete cycle of operations required to take e each exposure. Accordingly, means are provided for\ automatically engaging and disengaging jaw clutch pla'tes |34 and. |35 at predetermined points of the operating cycle, thus controlling the operating period of the mechanism, includ-.

ing'shaft |33 and metering drum'84 which is driven from clutch plate |35. In order to be disengaged fromclutch plate |35, plate-|34 is slidably keyed to shaft |3| and has a collar 23| integral therewith, said collar being adapted to cooperate with a yoke 232. Yoke 232 is formed.

integrally with a pivotal arm or lever 233 on which a roller follower 234 Fig.- 10) is mounted, the latter being actuated by a cam 235 and being urged into contact withlsaid cam by a coil assai/as spring 203a. fixed at oneuend to conecasting and at the other end' to arm 203. Rotation of said cam oscillates arm 203 and thereby actuates collar and controls the engagement of clutch |94, |95. y

Cam 205 isl mounted on a shaft 206 which is driven through a worni and worm wheel drive, comprising worm |93 and a worm wheel 201, from shaft |9| and, therefore, is continuously rotating-during the cycle of operations; The

gears are preferably designed so that cam 2h05l moves a single revolution during each cycle of operations and said, cam is designed to\ keep clutch` |94, |95 engaged during approximately a halfL of said cycle, the film being accurately metered by drum 64 during said half cycle.

` For the purpose of raising pressure plate 63 once during each cycle of oper-ations', to free the A lm for metering in accordang with the abovedescribed method, means are provided for actuating rod' |42 (Fig.- 8) which, as hereinbefore described,y operates the mechanism for raising and lowering said pressure plate. v(Fig. 1) is slidably mounted in andv extends .through hollow shaft 200 and, when jaw clutch |02 is drivingly engaged, said rod is adapted to n move upward and have' its upper endl bear against the lower end of rod |42, lifting the lat- `ter rod and raising pressure plate 63 through arm |4I. The reciprocal movement yis imparted to rod 206 through a cam mechanism comprising mounted and which guides said rod during reciprocal motion thereof. Another lug 226' provided with an opening therein is also formed integrally with bracket 223 and serves as a guide for a rod 221rxed to plate 2|9 and extending upwardly therefrom parallel to rod 220, said lugs and said rods keeping plate 2|9 horizontal during the collapsing and expansion of bellows 2|5.

When pinion 22| rotates in a clockwise direction, asl viewed in Fig. 13, rack or rod 220 is moved' downward, said downward motion being 'transmitted by plate 2|9 to bellows 2I5, collapsing said bellows against 'the resistive force of 'springs 2|6. This rotation of pinion 22| is accomplished by a pawl 226 (Fig. 12) pivotally mounted to a gear 229 and rotatable therewith,

said pawl engaging notches in a hub 230 of saids pinion and being held in engaged position with said notches by a plate spring 23| xed to'said, gear. vPlate spring 23| applies a counterclock` wise torque to pawl 228 which, when overcome,

' causes said pawl to pivot in a'clockwise direction A rOd 208` a roller cam follower 209 and a cam 2|0, the vforfilm in the base plane of pressure plate 63, presr sure means comprising a plurality of bellows are provided, said bellows being adapted to expand rapidly from a collapsed position andy thus have the pressures therein materially decreased. In

the illustrated embodiment, two bellows 2|5, 2|5

y(Fig. 10) are shown as being supported on a member 2 I6 carried on casting |15, said member having an opening 2|1 (Fig. 11) therethrough which connects each of said bellows to conduit |52-and, therefore, to chamber |46. Thus, a suction, if created in said bellows, will also `exist in said chamber and in grooves |43, urging the film into contact with pressure plate 63.

Bellows' 2|5 are collapsed by suitable means against the resistingyforce of coil springs 2I8 located within said bellows and, when said collapsing means are released, said springs tend to return` to normal position, thereby rapidly expanding the bellows. The collapsing means comprise a plate or bar 2|9 which extends over and rests upon the tops of said bellows and may be fixed thereto, and a rod 220 xed to said bar intermediate the ends thereof.' Rod 220 has gear .teeth formed thereon and constitutes a rack which meshes with a pinion 22| freely mounted for rotation on a shaft 222, said shaft being and release hub 230', thereby releasing pinion 22| for free rotation about shaftc222.

Gear 229 is mounted on shaft 222 and is driven by a gear `232 xedvto ashaft 233, the latter gear being adapted for continuous rotation during the operating cycle and accordingly continuously drivingg'ear 229 in a clockwise direction. Shaft (233 is driven by a worm and Worm wheel 234 from a shaft 235 which.. in turn, is driven through gear |90, thereby constituting a drive from motor |64a.

For reasons hereinbeforestated, a suction is to be created' on the pressure plate side of the lm when said pressure plate is about to be lowered and again at th'e moment when the photograph is taken', thus requiring that bellows 2|5 expand twice during a singleloperating cycle. Accordingly, means are provided whereby pinion 22| is automatically released from gear 229 when pressure plate 63 is about to be ilowered, causing bellows' 2|5, which `up to that part of the cycle are being collapsed, to expand and create the desired suction. For this purpose, a bracket 236 (Fig. 12) suitably fixed to casting |15 has an arm 231 extending vertically upward therefrom, said A arm being adapted to engage alug 236 which is integral with pawl 226 and to apply a clockwise torque to saidpawl by engaging said lug. Ap-

` plication of said torque to said'pawl causesv the journalled in and extending between brackets l H223 andf22lel1red to cone casting |15. A lug 225 is formed integrally with bracket 223 and has an opening therein in which rod 220 is same to befreleased from hub 230 and thereby permits bellows`2|5 to expand and move the lm into contact with pressure plate 63. Therelease of said pawl from said hub is preferably timed, by suitable choice of gearing and suitable positioning of arm,231, to occur substantially at the moment when pressure plate 63 reaches the focal plane determined by surface |2 As gear 229 continues to rotate, pawl 223 moves past arm 231 and again operatively engages hub 230, thereby collapsing bellows 2|5 for a second time. `When the bellows are fully collapsed, gear- 229 has rotated a single revolution during the cycle and assumes a position corresponding to the initial position held thereby.

In order to createa suction and simultaneously expose the film, novel means, to be described, are provided whereby the release of the bellows also controls the operation of the shutter mechanism.

` Release of the bellows for the second cyclic during assembly.

expansion is accomplished either manually or autortically by means shown in' Figs. 10 and l1. lhe manual means comprise a push but ton 238 slidably mounted in a supporting arm 239 of ahandle 248, said arm being fixed to or fulcrumed for pivotal movement about a horizontal axis in a groove 243 in arm 239, by means of a ,screw or pin 244 mounted in said arm. The otherend of lever 242 extends through casing |16 into cone 24 and is adapted to engage an arm 245 of a pivotal member 246, said member being mounted for rotation about an axis perpendicular to the pivotalaxis of lever 242, and being held in position on said axis by nuts 241. Member 248 consists of a fiat plate having two arms 245 and 249 integral therewith and disposed on -opposite sides of the axis of rotation. Arm 249 extends parallel to said' axisand engages a pin 250 slidably mounted in a support 25| fixed to bracket 224, said pin being yieldingly held against downward movement by suitable means such as a spring 252" positioned between said support and abracket 253 secured to said pin. Support 25| is so mounted relative to gear 229 (Fig. 12) that pin 250 is directly over pawl 228 when the latter has caused bellows 2|5 to be collapsed'for a second time; said pin being adapted to move said pawl clockwise when moved downward. l

To disengage pawl 228 from hub 238 and expand bellows 2|5, push button 238 is depressed against the resistance of coil spring 24| to actuate lever` 242, thereby raising arm 245 of member 248 and lowering arm 249 by overcoming the resistance of spring 252. As arm `249 and therefore pin 250 are moved downward, the latter moves pawl 228, releasingrpinion 22| and permitting springs 2|8 to expand bellows 2|5, thus creating a suction in the grooves |43 of pressure plate 83 and manner so as to be operative between the lenses, is adapted to be moved at various speeds to admit a predetermined amount of light through the lenses despite varying atmospheric conditions. Because of the rapidity with which the curtain must move v in order to correctly control the passage of light, sudden forces of varying magnitudes are being intermittently applied in different directions to said curtain. In the present invention, in order to reduce or entirely eliminate the possibilities of "some form of deformation in curtain 259 due to said forces, a

novel curtain is provided. The latter is pref-y erably vcomposed of a suitable ilexible metal such as beryllium copper, although a thin, ilnely meshed, metal screen which is impregnated with rubber or other opaque material may be successfully utilized.

Novel curtain drums or rolls 288 and 28| are provided for novelly mounting and driving curtain 259, and each comprises (Figs. 14 and 19) a central shaft 262 journalled for rotation in a substantially square frame or support 268. A pair of collars 264, 284, loosely mounted on central shaft 262, are secured to a hollow cylindrical drum 265 concentric with the axis of said shaft.

`Drum 285, to which curtain 259 is fixed and about which it is wound, is driven through a yielding drive comprising a plurality of wires 268, two beingv shown in the illustrated embodi- 1 vment, which are slidably iixed at the ends in thereby causing the film to adhere to the base 4 plane of said pressure plate.

A solenoid 254, shown in the illustrated ernbodiment as positioned beneath pivotal member 246, is adapted, when energized, to attract said member and thereby operate the pawl releasing mechanism above described. The solenoid is utilized to effect an automatic Vcontrol of the releasing mechanism by being connected to' a source of electrical energy through a switch controlled by an interval meter.

f Shutter mechanism and lens A wide angle lens comprising elements 255 i Fig. 20) is supported by members 256 which are in turn supported and accurately aligned on flanges 251 and 258 provided therefor in cone casting |15, said members being secured to said flanges by means such as screws 258a. It will be noted that the cone casting carries the lens members and also provides the surfacer for determining the plane of the film, thus minimizing the possibility of misalignment between the lens and the film plane when the former is The image of the object to be photographed is focused on the film by said lenses and irn-l positioned collars 264 and rigidly xed aty the centers in a vcollar 251. The latter collar is pinned to shaft 262 and rotatable therewith when said shaft is driven through bevel gear 268 mounted thereon. As a result of the above-described structure, drum 265 is driven through said wires and is permitted a limited degree of rotation relative to shaft 262, dependin upon. the resiliency of wires 286 and the manner in which said Wires are held in collars 264.

BothI of the curtain rolls are similarly constructed and curtain 259 is suitably wound on said rolls and is adapted to be moved from one roll to the other exposing a new frame of film each time it is moved. Since drums 265 are exactly alike in construction and dimensions, the eifective diameter of one roll decreases as that of the other increases when the curtain unwinds from the former to the latter during an ex'- posure, due to ther increasing number of curtain thicknesses upon the latter. If, under these circumstances, drums 265 are driven at the same angular velocity, a difference in linear velocities would arise at the drum peripheries tending to wind the curtain at a more rapid rate than it is being unwound and therefore causing an excessive tension or elongation to be produced in said curtain. Accordingly, the yielding drives are provided for the drums whereby, although the central shafts are driven at equal speeds. the

Adrums are permitted relative rotation thereto,

sion. Furthermore, the initial sudden load im parted to-V the shaft when an exposure is to be made is absorbed in part by the resiliency of the drive, causing a more. uniform application of the force to the curtain.

It is highly desirable that the lens elements,

once accurately fixed in position, remain undisturbed thereafter, and therefore frame 263 is suitably constructed and curtain 259 and rolls 260 and 26| are` suitably mounted thereon, to have the shutter-mechanism adapted for ready removal from operative position as a unit without affecting the lens. As shown, frame 293 comprises a U-shaped casting having the two parallel arms 269 ,and 21|! thereof supporting rolls 268 and 26|, respectively, and said arms and rolls are fitted into operative position by lnserting frame 263 into conecasting |15 with the openY end of the "tl-@shaped casting foremost. Curtain 259 fits betweenthe lenses and a thin plate 21| may be secured across the open end of said casting in the horizontal plane of said curtain, thus adding to the rigidity of the structure and not detracting from its removability, since said plate, when frame 263 is inserted or removed, passes freely between the lens elements along with curtain 259.

Curtain rolls 268 and 26| are adapted to be driven by means which automatically. alternate the direction in which said/drums'are rotated after each exposure causing the curtain to be alternately wound and u nwound from each roll and to expose a nlm frame each time it is moved across the lensesf As illustrated in Flgs.` 1li and 16, 'said curtain rolls are driven through bevel gears 268 mounted on central shafts 282 of Said rolls and said gears mesh with a pair of bevel gears 212 secured to a shaft 213. Shaft 213 is4 in turn adapted to be driven through either of two gears 214, 21,4 loosely journalled thereon and driven in opposite directions by an annular gear 215. A sleeve 218 slidably keyed between gears 214 to shaft 213 for rotation with said shaft has a collar 211 integral therewith' and is provided with vaxially extending lugs or pawls 218 on each end thereof. The hubs of gears 214 extend bevond the faces of said gears in the direction of sleeve 216 and have suitable openings 219 therein adapted to be engagedby lugs 218. When sleeve 216 is moved in the direction of one of gears 214, that gear is engaged by those of lugs 219 on the adjacent end of said sleeve and a driving connection in the nature of a jaw coupling from annular gear 215 to curtain rolls 28|) and 26| is established.

`When an exposure is taken, gear 215 is driven at a predetermined high velocity, by means to be described, and moves curtain 259 and the opening therein past the lenses by means 'of the connection above described. If this movement of the curtain is, for example, to the right, as viewed in Fig. i4, then said curtain is wound upon drum 29| and for the next exposure must be unwound therefrom and moved in the opposite direction. Accordingly, during the interval between exposures while the new frmne of iilrn is prepared for exposure, sleeve 21@ is automatically moved into engagement with the other of pinned to shaft 282 between supports 283 is provided with a groove 285 in the base thereof which extends in a direction perpendicular to the axis of said shaft. A pin 286 eccentrically mounted on or formed with rotary disc orplate 281 cooperates with said groovev and is adapted to translate the rotary motion of said disc into reciprocal movement of, member 284, thereby actuating sleeve 216. It will be understood that any other lsuitable linkage, such as a crank and connecting rod, could be employed to impart reciprocal movement to member 284 or tov sleeve'216 directly. In the illustrated embodiment of the invention, disc 281 preferably rotates a half revolution during each operating cycle, moving sleeve 216 from one extreme position to the other during the single cycle, i. e. out of engagement with one of gears 214 and into engagement with the other. Disc 281 is preferably integral with a shaft 288 driven by a bevel gear 286 which mesh' also drives the cams that control the pressure plate and the metering roll mechanisms.

A high turning torque must necessarily be ap- "plied to gear 215 in 'order that said geanmay rotate at a suflicient angular velocity to produce desired exposure speeds 'of curtain .259. To impart such a torque to said gear, a spring drive comprising a drum 29|, a spring 292 and a shaft 299 is provided having said shaft pinned or otherwise suitably secured to said gear. spring zsz, as shown in Fig. 15, is wound about shaft 293 and is fixed at one end to drum 29 and at the other end to said shaft and is adapted to drive the latter, thereby driving gear 215. Means, to be described, are provided whereby shaft 293 is held against rotation during the operating cycle while `drum 29|. rotates relative thereto in a direction towind spring 292. Aitorque tending to turn said shaft is thus set up in the spring, the magnitude of the torque depending on the amount of relative rotation between drum 29| I drive. The drive comprises a pair of bevel gears of shafts 298 and 299.

gears 21d thereby reversing the drive to the curmounted for reciprocal movement in supports or brackets 2&3 which are an integral part of frame '263. A member 284 mounted on and, suitably The latter is, in turn,4

296 and 291 mounted for rotation on shafts 298' and 29 9, respectively, said shafts being journalled in a worm gear 30d. Worm gear 366 has suitable openings therein for receiving gears 296 and 291, and is freely mounted upon a shaft 38|. rotating about an axis Athat is perpendicular to the axis A bevel gear 392, shown integral with shaft 38|, meshes with gears 296 'and 291 and is adapted to drive gear 29,5 when gear 399 is fixedagainst rotation and when shaft 30| is driven by a gear 363 pinned to said shaft.

Gear 303 operatively engaged by a bevel gear 994, shown in Fig. l, the latter being mounted on a shaft 395, and said shaft is adapted to'be driven by a worm andfworrn wheel drive 30G from shaft 96 (Fig. 10). Accordingly. drum 29| is driven for the same interval that the main lm is being metered, and the spring drive is wound by said rotation, being prepared for moving curtain 259.

Novel means operable in conjunction Vwith bellows 2|5 are provided whereby shaft 293 is held against release while drum 29| winds spring 392 and whereby said shaft'andf therefore, shutter second cyclic expansion of said bellows. 'I'he means comprise a pair of cams or ratchet wheels 301 and 308 of similar peripheral contour each being provided with a single notch, and both beby suitablel means, such as rivets 309. During the maior portion of the cycle of operations. shaft 293 is held against release, i.. e. against clockwise rotation as viewed in Fig. 17. by a lever 3|0 pivotally mounted about a pin 3| An arm 3|2 ofI said lever is adapted to engage the notch in cam 308 thereby holding the same against rotation in a clockwise direction. A second arm 3 I3 `also formed with said lever bears against the periphery of a cam 3M mounted on shaft 288, and.is yieldingly` held in contact with said cam by a coil spring 3|5. Coil spring 3|5 is fixed at one end to arm 3|3 and at the other end to a supporting plat-3|6 in which pivot pin 3|| is mounted and which is secured by means such as screws 3|1 to frame 283. Cam 3M, as shown, comprises a circular disc having two symmetric and radially projecting portions 3|8 and 3|9 integral therewith and disposed diametrically op- DOSit-e each other and adapted to pivot lever 3|0 in a clockwise direction when brought into contact with arm 3|3. Shaft 288 which actuates the means for reversing the shutter drive rotates a half revolution every cycle of operations and cam 3H is suitably positioned on shaft 288 to have lever 3|0 pivoted thereby substantially at the end of the cycle.

When'lever 3|0 isV pivoted in a clockwise direction, as viewed in Fig. 17, arm 3| 2 moves away from cam 308 and becomes disengaged from the notch therein, thereby permitting rotation of said cam and of shaft 293. At this .point in the cycle of operation,- the bellows 2|5 have been collapsed a second time and a pin 320, actuated by said bellows in a manner to be hereinafter described, is in position to engage the notch in cam 301.

This limits the rotation of shaft 293 to a displace` ment that is only sulcient to move the notch in cam 308 past arm '3|2 and to free shaft 293 from said arm. Shaft 293 is then held against rotation by pin 3-20 and when said pin is disengaged from the notch in cam 301, shaft 293 is rotated substantially a single revolution and curtain 259 is moved thereby to expose the lrri.4

The total rotary movement of shaft 293 during each cycle of operation will not exceed a single revolution, since cam 308 is held by lever 3|2 at the start of the operation and at the completion of the cycle after' an exposure has been taken, i. e. after pin 320 has been disengaged from cam 301, said lever again engages and holds said cam.

In order that the release of shutter curtain 259 be concurrent with the second expansion of the bellows, pin 320 is suitably secured to or formed integrally with a rod 32|, said rod being slidably mounted for reciprocal movement in a bracket or bearing member 322 which is a part of supporting member 3| 6. A bushing 323 is fixed in member 322 and a collar 324 is attached to rod v32i, so that a compressed coil spring 325 interposed between said bushing and said collar tends to keep pin 320 in engagement with cam 301. A portion of rod 32| extends rearwardly in a horizontal plane substantially at right angles to the axis of the part slidable in bracket 322 and serves as a cam follower, engaging a cam 326 fixed to plate 2|9 of the bellows structure.

expanded, said cam takes a position, shown by broken lines in Fig. 17, having been moved upward and having caused rod 32| and pin 320 to move to the right and away from cam 301 to clear the. notch therein.

Bellows 2|5, for reasons hereinbefore disclosed, are expanded twice during the operating cycle, and both times pin 320 is moved to the right and away from cam 301. Nevertheless, the first expansion does not release the shutter mechanism as shaft 2931s then held against Arotation by arm 3|2 of lever 3|0 which is in engagement with the notch in cam 308. However, just prior to the completion of the second collapse of the bellows, cam 3|! pivots lever 3|0 and permitsv shaft 293 to rotate the --Iimited amount necessary tokeep arm 3| 2 disengaged from the notch in cam 308 for a complete revolution so that shaft 293 isv then held against rotation only by pin 320. Accordingly. when the bellows are expanded for a second time, shaft 293 is freed` for substantially a complete revolution and 'moves 'shutter curtain 259 for an exposure. Thus, the shutter mechanism can be actuated to expose the nlm only after the cycle of operations, metering and positioning the nlm, is completed. Y

In order to control the operation of motor |84a, le'ver 3|0 has a horizontally extending arm 3|0a (Fig. 17) adapted to actuate a switch 3| 0b. The latter, which is suitably mounted on cone casting |15, is connected in the circuit of motor lala and breaks said circuit whenl said lever is rotated clockwise as byvprojection 3|8 or 3|9 of cam 3H. After the motorcircuit is thus broken, the inertia of the mloving parts continues the rotation of said cam until the projecting portion causing the break moves past arm 3|3. However, the motor circuit is not closed again by this additional rotation but instead remains open, lever 3|0 being held in the displaced position by cam 308 until the vshutter is released. Accordingly, the motor will not resume operation until a new frame of film must be prepared for exposure.

Means are provided whereby the speed of curtain 259 and therefore-the exposure timing may be selectively controlled, said means comprising a knob 328 or other manual control (Figs. 1 and 14) readily accessible from the exterlor of casing |18. Knob 328 is operatively connected to a bevel gear `329 through which said knob is adapted to drive. a second bevel gear 330 mounted on a shaft 33|. A worin 332 afxed to or integral with said shaft meshes with gear 300 thereby completing a drive from knob 328 to drum 29|, since rotation of gear 300 isvtransmitted to said drum through gears 298 andv 291 and gear 285. The speed of gear 215 and therefore the speed o f curtain 259 depends on the torque applied thereto by spring 292 which in turn is a function of the rotation of drum 29| relative to shaft 293i. e. of the tension induced in said spring by rotation of drum 29| while shaft 293 is held against rotation. Knob 328 is adapted to vary the effective torque applied to shaft 293 by increasing or decreasing the initial tension in spring 292. crank |84 or motor |84a, causes drum 29| to rotate a single revolution. and sinceshaft 293 Since the driving means,\ 

